Interaction of coenzyme M and formaldehyde in methanogenesis.
Chemical reaction of coenzyme M, sodium 2-mercaptoethanesulphonate (HS-CoM, Na+), and formaldehyde formed sodium 2-(hydroxymethylthio)ethanesulphonate (HOCH2-S-CoM), whereas reaction with the ammonium salt of HS-CoM yielded iminobis-[2-(methylthio)ethanesulphonate], monoammonium salt [NH = (CH2 - S - CoM)2]. In water, NH = (CH2 - S - CoM)2 decomposed to 2-(aminomethylthio)ethanesulphonate (NH2CH2 - S - CoM) and HOCH2-S-CoM. NH-2-CH2 - CoM was degraded further to form more HOCH2-S-CoM. The structures of these coenzyme M derivatives were confirmed by i.r. and n.m.r. spectroscopy and by elemental analysis. When added to cell extracts of Methanobacterium thermoautotrophicum, methane was formed from either HOCH2 - S - CoM or NH = (CH2 - S - CoM)2 at rates comparable with the rate of methane formation from the methanogenic precursor 2-(methylthio)-ethanesulphonate (CH3 - S - CoM). Formaldehyde was reduced to methane at similar rates. In addition, certain hemimercaptals, including thiazolidine and thiazolidine-4-carboxylate, were reduced, although at slower rates. The reduction of formaldehyde, thiazolidine, or thiazolidine-4-carboxylate required catalytic amounts of HS-CoM. ATP was required by cells extracts for reduction of each of these methane precursors.
D000255:Adenosine Triphosphate / Q000494:pharmacology; D019605:Euryarchaeota / Q000378:metabolism*; D005557:Formaldehyde / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008623:Mercaptoethanol / Q000031:analogs & derivatives*; D015080:Mesna / Q000378:metabolism*; D008697:Methane / Q000096:biosynthesis*; D010084:Oxidation-Reduction
D005557:Formaldehyde; D008623:Mercaptoethanol; D000255:Adenosine Triphosphate; D015080:Mesna; D008697:Methane